This is a bit of a trivial question, but as I don't know the answer immediately I thought I'd just ask.

Given the integral $\int_{0}^{t} \int_{0}^{t} f(x,x') dx dx'$, what is $\frac{\partial}{\partial t} \int_{0}^{t} \int_{0}^{t} f(x,x') dx dx'$? It looks a bit like differentiating under the integral sign, but I'm not sure how to handle it.

'as I don't know the answer immediately I thought I'd just ask" ... is this a polite way of saying you've thought about it a bit and can't remember how to do it? (and FWIW it is not like differentiating under the integral sign; moreover, without some conditions on $f$ it's not clear to me that you can say anything precise)
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Yemon ChoiApr 1 '10 at 18:25